Once the time is up, press "Cancel" and wait a couple of minutes. Then, very carefully and using a potholder, turn the pressure release valve to "Venting." Wait till all the steam is released completely, around 4-5 minutes, and open the lid.
Stir the soup with a wooden spoon and let it cool slightly, just a few minutes. Then, use your immersion blender on a low setting to puree the soup for around 30 seconds or less. Add the salt and pepper, and stir thoroughly again.
Image Source: Michelle Chahine Sinno